Trailer structures

ABSTRACT

Trailer structure having a tilt limiting loading ramp and an improved structural side member forming an adjustable axle mount and having a load tie down track is described. The trailer has a load supporting bed and utilizes a load tie down system having tie down tracks at each side and one or more additional tie down tracks at selected locations on the load supporting bed. One or more tie down devices are selectively positionable in each tie down track and are used to restrain various loads including various wheel supported loads. To accommodate a low trailer profile an improved tongue adaptor is provided. A fender mount structure to cooperate with the improved structural side member is also described. Improved loading ramp structures, including a tilt-bed loading ramp a tilt limiting structure for limiting the angle of bed tilt for use on a tilt-bed trailer are shown. A rack structure to mount to the load tie down tracks in the structural side members is shown.

CROSS REFERENCED TO CO PENDING APPLICATION AND ISSUED PATENT

[0001] This divisional application is related to commonly owned U.S.Pat. No. 6,439,814, issued Aug. 27, 2002, and was co-pending U.S. patentapplication Ser. No. 08/978,781, filed Nov. 26, 1997, and entitled“Trailer Structure & Tie Down Mechanism”; and is incorporated byreference.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] This invention relates to improvements in trailer structures;and, more particularly, to improved structural members. Still moreparticularly, the invention relates to improvements in trailers utilizedfor utility loads including wheel-supported loads.

[0004] 2. State of the Prior Art

[0005] The use of utility trailers to transport all terrain vehicles(ATV's), riding lawn equipment, riding golf carts, and otherwheel-supported loads are known. These include wheel-supported loadshaving two, three, four, or more wheels as well as wheel driven tracksystems. Various ramp devices have been developed to aid in the loadingof such wheel-supported loads from the ground surface to the bed of thetrailer. It has long been recognized that wheel-supported loads havingaligned wheels and those having four or more wheels arranged in tandempairs can be difficult or impossible to load if the ramp structure istoo short and the angle of the ramp to the trailer bed is great enoughfor the wheel-supported load to engage the juncture of the ramp and thebed causing the leading wheels to fail to contact the surface of thebed. This high centering results in the load not being supported by oneor more of its wheels. This phenomenon is particularly apparent invehicles such as riding lawn mowers when the mowing deck is suspendedbetween the wheels, ATV's, golf carts, and the like.

[0006] In fixed bed utility trailers, the problem of high centeringloads has been addressed by making the ramp structure longer and longerto minimize the angle at which the ramp affixes to the trailer bed.

[0007] It is known in the prior art to provide a loading ramp that ishingedly mounted to a utility trailer bed and is operable to be raisedforming an extended end gate when the trailer is in motion. Varioustypes of hinged ramps have been developed, and have utilized varioustypes of structural materials. The ramp structures of course had to beof sufficient strength to support the loads and had to be constructed toallow sufficient traction for wheel driven loads to move up the ramp.Solutions involving wooden structures were heavy, and required eithersome form of nonskid surfacing or cross cleats to engage the wheeldriven load.

[0008] A common type of prior art ramp involves the use of meshed metalsheets supported on a sufficiently strong frame to support the load. Inall cases the hinge mounted extended loading ramps are heavy andunwieldy to handle. They also cause an extensive wind drag when beingtowed due to the fact that they present a substantial surface that canextend five or more feet above the surface of the trailer bed.

[0009] It is desirable to provide a loading structure that minimizes theamount of material used in the loading ramp to minimize the cost ofconstruction and maximize the ease of use. It is also desirable toprovide a loading ramp structure that minimizes the air drag with itsattendant loss of fuel efficiency for the towing vehicle, whileproviding positive traction for wheel driven loads.

[0010] Tilt-bed trailers were developed to assist moving loads from aground surface to the trailer bed by causing the bed to tilt such that aloading edge would engage the ground surface. As a wheel-supported loadis moved from the ground surface onto the trailer bed, the bed isallowed to rotate back into contact with the tongue such that the bedcan be affixed to the tongue and the load moved. The prior art tilt-bedtrailers work reasonably well where the length of the tilt-bed issufficiently long to allow the angle of the bed to the ground surface tobe relatively small. For short bed utility trailers with a tilt-bed, theproblem is often encountered that the leading structure of the loadimpinges on the tilted bed at a point that inhibits the wheels frombeing allowed to come in contact with the trailer bed. A further problemexists, particularly with riding lawn mowers and the like, of a trailingstructure engaging the ground surface as the load is moved onto the bedsuch that the rear wheels are lifted from contact with the ground or thetrailer bed. Of course these conditions exist in reverse when the loadis to be removed from the trailer bed to the ground surface.

[0011] The shorter tilt-bed trailers have the additional concern thatthe angle of loading is relatively steep. If care is not taken whenmoving the wheeled load onto the bed, the weight distribution can gopast the balance point too quickly and cause the trailer bed to rotatesharply to the level position thereby causing a substantial jolt whenthe bed impacts the tongue. If the wheel-supported vehicle is riddenonto the trailer by a human operator, such a jolting action isuncomfortable and in some instances can cause injury.

[0012] It is desirable to provide an improved structure for use withtilt-bed utility trailers that minimizes the deficiencies andundesirable features of prior art tilt-bed trailers.

SUMMARY OF THE INVENTION

[0013] The present invention includes a lightweight aluminum trailerframe structure for use with a tilt-bed trailer and having a tiltlimiting loading ramp coupled to the frame. The tilt limiting loadingramp includes a tilt limiting structure to engage the ground when theframe is tilted for loading, the range of tilt limitation being suchthat a trailer bed supported on the frame is substantially aligned withthe ramp. The tilt limiting loading ramp is constructed of membersarranged across the width of the trailer bed and spaced apart asufficient distance to minimize wind drag when raised and the trailer isbeing towed, but close enough to prevent the wheels of a wheel supportedload from passing between them as the load is being moved onto thetrailer bed. The arrangement is such that the height of the tiltlimiting loading ramp as it relates to the height of the tilt limitingstructure establishes a predetermined ratio for establishing the slopeof the ramp. This ratio is selected depending upon the length of thetrailer bed to establish the desired alignment between the bed and theramp.

[0014] Another aspect of the invention is an improved side structuralmember constructed of extruded non-corrosive metal, with one such memberutilized at each side of a trailer bed frame. Each side structuralmember is cut to a predetermined length to establish the desired lengthof the trailer bed and includes a number of functional features inaddition to providing frame structure. The side structural memberincludes an upper portion extending upwardly from the bed surface andhas an upper channel for providing strength to the side structuralmember and for cooperating in mounting auxiliary fixtures. A face memberextends downwardly from the upper portion and has a lower extremity. Theface portion has an inner surface to which is integrally formed anelongated retention channel extending along the length of the sidestructural member. This retention channel functions in cooperation withslidably positionable tie-down loops to allow loads to be cross-tiedbetween the oppositely disposed side structural members. Such crosstying is particularly beneficial for wheel-supported loads. Theintegrally formed retention channel is also used for mounting anauxiliary rack to the trailer structure. In addition to the upperportion, the face portion, and the integrally formed retention channel,an axle mounting and positioning structure can also be utilized. In suchan additional configuration, an inner member is integrally formed anddownwardly extending from the elongated retention channel and having alower extremity. A lower channel structure is integrally formed andcoupled to the lower extremity of the face portion and the lowerextremity of the inner portion. The lower channel structure has adownward channel opening and a predetermined shape including a mountingstructure having oppositely disposed ridge mounting surfaces. The lowerchannel structure is adapted for use in combination with a matingslidable axle support member that has a predetermined length and one ormore threaded holes therethrough to mate with and slidably engage theoppositely disposed ridged mounting surfaces. This structure allows asupported axle to be moved to a predetermined desired position along thelength of the side structural member and to be clamped in place whenmounting bolts are tightened.

[0015] An improved fender mounting bracket for use with a low profiletrailer with the bed mounted low between the wheels is provided. Thefender bracket includes an upper portion to be gripped by the upperchannel of the side structural member, a middle portion to which areaffixed outwardly extending mounting structures, and a lower portion tobe held in place in cooperation with an associated slidable axle supportmember. The mounting structures are outwardly extending and each includea longitudinal nut retention channel to allow one or more bolts throughan associated fender to be tightened to associated captive nuts heldwithin the channel. The mounting structures can also be utilized assupport for steps at the front and the rear of a fender to allow anoperator to step up onto the trailer structure.

[0016] Another aspect of the invention for low profile tilt-bed trailersis a hitch level adapter selected to have a height to maintain a trailertongue at a predetermined level when hitched to a towing vehicle. Atrailer tongue having oppositely disposed ridges along at least aportion of its length is rotatably coupled to the tilt-bed trailer framestructure. The hitch adapter includes an upper box beam structure havingan upper surface for mounting a trailer hitch. A pair of downwardlyextending oppositely disposed gripping members are provided to cooperatewith and grip the ridges on the trailer tongue. Bolts through thedownwardly extending members and the trailer tongue hold the hitchadapter firmly in place.

[0017] An improved tilt-bed trailer has supporting means for supportingtrailer bed means with such supporting means including side structuralmeans for mounting a wheel assembly. Bed means are mounted on thesupporting means for supporting a load. Tongue means are rotatablycoupled to the supporting means for allowing the trailer to be towed,and for allowing the supporting means to rotate the bed means withrespect to the tongue means. Tongue means are provided for releasablycoupling the tongue means to the supporting means to allow the bed meansto be tilted when released. Ramp means are hingedly coupled to thesupporting means for loading and unloading a wheel supported load, withthe ramp means including tilt limiting means for engaging a loadingsurface and limiting the slope of tilt of the bed means in a manner suchthat the ramp means and bed means are substantially aligned when loadingor unloading a wheel supported load. The side structural means includesmeans for releasably holding slidably adjustable tie down means fortying down a load. The side structural means can further include amounting means for adjustably mounting a wheel assembly at any desiredposition along the length of the side structural means. Auxiliary fendermounting means can be coupled to the side structural means for mountingan associated fender in a desired position along the side structuralmeans. A height adapting means is provided for cooperation with thetongue means to establish a predetermined height adjustment for anassociated hitch with respect to a towing vehicle.

BRIEF DESCRIPTION OF THE DRAWINGS

[0018]FIG. 1 is a partial view of a tilt-bed trailer carrying an allterrain vehicle;

[0019]FIG. 2 is a side view of a tilt-bed trailer with a tilt limitingloading ramp raised;

[0020]FIG. 3 is a side view of a tilt-bed trailer with the bed tilted toa degree limited by the tilt limiting loading ramp;

[0021]FIG. 4 is a top view of the tilt limiting loading ramp;

[0022]FIG. 5 is a face view of the tilt limiting loading ramp;

[0023]FIG. 6 is an end view of the tilt limiting loading ramp;

[0024]FIG. 7 is a partially exploded view of a tongue adapter mounted toa trailer tongue and a ball trailer hitch;

[0025]FIG. 8 is a cross-sectional view of a side structural member;

[0026]FIG. 9 is a cross-sectional view of a fender mount bracket;

[0027]FIG. 10 is a partial perspective view of a fender supportstructure mounted on a side structural member;

[0028]FIG. 11 is a three-dimensional view of a slidable axle and fendermounting member;

[0029]FIG. 12 is an end view of the slidable axle support memberslidably engaged within the mating channel in the side structuralmember;

[0030]FIG. 13 is a cross-sectional view of a tie down track for use withaluminum bed members;

[0031]FIG. 14 is a partial rear view of a wheel, fender and axleassembly mounted on an adjustable axle support mechanism;

[0032]FIG. 15 is a three-dimensional view of a loop tie down device;

[0033]FIG. 16 illustrates a releasable structure for use with loop tiedown device;

[0034]FIG. 17 is a cross-sectional view of a front structural member;

[0035]FIG. 18 is a cross-sectional view of a rear channel structuralmember;

[0036]FIG. 19 illustrates a railing bracket;

[0037]FIG. 20 illustrates a railing bottom holding member mounted to aside structural member; and

[0038]FIG. 21 is a broken three-dimensional view of a mounted railingbottom member.

DESCRIPTION OF THE PREFERRED EMBODIMENT

[0039]FIG. 1 is partial view of a tilt-bed trailer carrying an allterrain vehicle. The trailer 10 has a bed 12 supported by a pair ofwheels 14, with bed 12 rotatably coupled to tongue 16. Tongue 16 iselongated and has oppositely disposed channels 18 running along itslength. A suitable tongue is described in U.S. Pat. No. 5,421,612entitled Trailer and Tongue Structure, issued to Wayne G. Floe. Othertongue structures could also be utilized. Bed 12 is supported betweenside members 20 and is supported by front member 22. A rear member (notshown) supports the bed 12 and a hinge structure (not shown) formounting loading ramp 24. A railing structure 26 is made up ofspaced-apart railing members 28 mounted on a number of posts 30 and isaffixed to side members 20, as will be described in more detail below.Wheels 14 are supported by an axle (not shown), with the bed 12 and itssupport framing mounted between the wheels and low on the axle toprovide a low profile. The fenders 32 are mounted to the side structuralmembers 20, and are constructed of metal or high density plastic. Afront step 34 and a rear step 36 allow a user to easily step up to enterthe trailer. An optional step structure can be provided at the top offender 32. Lights or reflectors 38 and 40 are mounted to steps 34 and36, respectively.

[0040] The tongue 16 has an adapter 42 mounted at its leading end, andhas a ball hitch 46 mounted to the adapter. The adapter 46 is configuredto cooperate with the structure of tongue 16, and will be described inmore detail below.

[0041] The bed 12 is retained by release mechanism 48 that functions torestrain the bed 12 in a fixed relationship with tongue 16, or toselectively release the bed to allow tilting with respect to the tongue.A number of mechanisms 48 are available, such as a pin inserted throughmating holes in the tongue, rotatable catch mechanisms, spring loadedcatch mechanisms, and the like. A bed retention mechanism that slidablycooperates with the tongue structure is shown in U.S. Pat. No. 6,068,282entitled, Tongue Retention and Release Mechanism, issued to Wayne G.Floe, which is incorporated herein by reference. Such a bed retentionmechanism utilizes a gripping portion that cooperates with the channels18 in tongue 16 and a mounting channel supported by the bed structure. Atension device 49 operates to hold the mechanism 48 in fixed contact ontongue 16, or to selectively release mechanism 48 to move forward ontongue 16 to thereby release the bed to rotate.

[0042] The all terrain vehicle (ATV) 50 is supported on bed 12. Alongitudinal tie down track, or retention channel, 52 restrains a tiedown loop 53 in order to hold one or more tie down lines 53 a to holdthe AIV in place on bed 12. One or more tie down loops 53 can bedisposed along the length of track 52 to allow various configurations oftie down placements. The tie down track utilizes a track opening that isnarrower than the channel opening, and retention mechanism disposedwithin the channel, to which the tie down loop is affixed. A loadretention system that satisfies these requirements is shown in U.S. Pat.No. 6,439,814, entitled, “Trailer Structure and Tie Down Mechanism”,issued to Wayne G. Floe, and is incorporated herein by reference.Additional novel tie down structures incorporated in side structuralmembers 20 will be described below.

[0043]FIG. 2 is a side view of a tilt-bed trailer with a tilt limitingloading ramp raised. The low profile bed 12 is shown supported onsupport structure 57, which in turn is supported on tongue 16. Tiltloading ramp 24 is mounted by hinge structure 54 to a rear structuralmember (not shown) in an upright position, thereby forming an end gate.A tilt limiting structure 56 is affixed as a tilt limiting mechanism.The depth of the tilt limiting structure 56 is selected to stop the tiltof bed 12 when the tilt limiting structure 56 engages the loadingsurface with the tilt loading ramp 24 in alignment with the surface ofbed 12. The tongue 16 is rotatably coupled to support structure 57 byrotatable coupling 58.

[0044]FIG. 3 is a side view of a tilt-bed trailer with the bed tilted toa degree limited by the tilt limiting loading ramp. The loading ramp 24is substantially aligned with the surface of bed 12, with the tiltlimiting structure 56 in contact with the loading surface. The supportstructure 57 is rotated out of contact with tongue 16. As will bedescribed in more detail below, the tilt limiting structure 56 extendsacross a substantial part of the width of bed 12 and is of sufficientstrength to support the load as it rolls onto the surface of bed 12,while it functions to limit the level of tilt of the bed. By way ofexample, with a bed length of about nine feet, the height of tiltloading ramp 24 can be in the order of about two feet, thereby providingminimal wind drag when in the upright position and the trailer is beingtowed. Of course a greater height will reduce the angle of bed 12 withrespect to the loading surface, and a lesser height will increase theangle.

[0045]FIG. 4 is a top view of the tilt limiting loading ramp. As shown,the upper surface of loading ramp 24 has a number of longitudinalridges. These ridges provide traction as a wheeled load is driven ontothe trailer, additional structural rigidity to minimize bending ordeforming, and resistance to surface marring from use. Tilt limitingstructure 56 includes a longitudinal surface engaging portion 60 and apair of curved portions 62 that are affixed substantially perpendicularto loading ramp 24. In this configuration a support member 64 is coupledbetween portion 60 and loading ramp 24. This configuration is acceptablefor ATVs and the usual wheel supported loads that would be encountered,but for heavier than usual loads, it may be desirable to utilize one ormore additional support members 64.

[0046]FIG. 5 is a face view of the tilt limiting loading ramp. Loadingramp 24 has a lower member 66 that support hinge pairs 54 a, 54 b, and54 c. These hinge pairs are arranged to cooperate with mating hingeelements mounted on a rear trailer structural member, and to be held inplace with hinge pins (not shown). A top member 68 is parallel to lowermember 66. A pair of side members 70 and 72 are each coupled at a lowerend to lower member 66, and have curved portions 74 and 76,respectively, coupled to top member 68. Members 78 and 80 are spacedapart and are coupled at their respective lower end to lower member 66and at their respective upper ends to top member 68. Members 78 and 80have an I-beam cross-section in the preferred embodiment to providestrength, but these members could also have round or squarecross-section. Side members 70 and 72 have a channel cross-section inthe preferred embodiment, but it is understood that these too could havedifferent cross-sections. Cross members 82 and 84 are affixed betweenend member 70 and member 78; cross members 86 and 88 are affixed betweenmembers 78 and 80; and cross members 90 and 92 are affixed betweenmember 80 and side member 72.

[0047] With a loading ramp having a height of about two feet, and eachof the structural members having at least a one inch cross-section, thespacing between the cross members will not exceed eight inches. For ATVsand the like, this spacing is sufficient to engage the wheels and allowthem to “walk” up the ramp without falling through. If smaller wheeledloads are to be loaded, it may be necessary to provide additional crossmembers to engage the smaller wheels. In the preferred embodiment thecross members have a box channel cross-section and are of a dimension tofit within the channel of the I-beams and the channels of the sidemembers and are welded at their respective ends. In the preferredembodiment all of the members are manufactured from extruded aluminum tominimize the weight, provide a non-corrosive structure, and providesufficient strength. It is of course understood that other materials andfabrication techniques can be used without departing from the scope ofthe invention.

[0048]FIG. 6 is an end view of the tilt limiting loading ramp. Loadingramp 24 is substantially perpendicular to tilt limiting structure 56.With a ramp height of about two feet, it has been found to beadvantageous to provide a tilt limiting support 56 having a height ofabout six inches, thereby establishing about a 4:1 slope. As mentioned,the relationship of the height of ramp 24 to the height of tilt limitingsupport 56 can be adjusted to establish the desired slope ratio.

[0049]FIG. 7 is a partially exploded view of a tongue adapter mounted toa trailer tongue and a ball trailer hitch. Adapter 42 is utilized toposition the ball trailer hitch 46 at a height to accommodate a trailerhitch on a towing vehicle, and is primarily necessary for use with a lowprofile tilt-bed trailer. Tongue 16 has a cross-section 100 thatillustrates the longitudinal protrusions 102 and 104 along channels 18.Adapter 42 has a cross-section 106 and has gripping portions 108 and 110that engage protrusions 102 and 104, respectively. A pair of bolts 112and 114 affix adapter 42 to tongue 16. The adapter 42 has an uppersurface 116 to support ball hitch 46 with holes 118 and 120 in alignmentwith holes 122 and 124, respectively. When thus aligned, bolts 126 and128 are inserted through holes 122 and 124, respectively, and thencethrough washers 130 and 132 to nuts 134 and 136, respectively. Adapter42 is a dual box beam cross-section for strength, and is of sufficientlength engage tongue 16 and support the load applied at the hitch.Shoulders 140 and 142 engage the upper surface of tongue 16 and assistin keeping adapter 42 aligned along tongue 16. In the preferredembodiment, adapter 42 is fabricated from extruded aluminum, thoughother materials can be utilized. The height of adapter 42 is selected incombination with the trailer wheel radius to keep the bed 12substantially level when the trailer is hitched to a towing vehicle.

[0050]FIG. 8 is a cross-sectional view of a side structural member. Sidestructural member 20 has a portion 150 that is substantially at thelevel of the upper surface of bed 12. Portion 152 extends upwardly fromthe bed level and forms a raised portion at the sides of the trailer bedto assist in maintaining a load on the bed when being loaded. Portion152 has an upper longitudinal channel 154 extending along its length,and is coupled to face portion 156. An inner member 158 is substantiallyparallel to face portion 156. A retention channel structure 160 iscoupled to the upper end of inner member 158 and to portion 150, andforms a longitudinal retention channel 162 between longitudinalprotrusions 164 and 166. Retention channel 162 is primarily provided toallow securing loads at desired position along the length of sidestructural member 20, for cross tying and the like. Other uses will bedescribed below. A mounting structure 168 is coupled to the lower end offace portion 156 and the lower end of inner member 158. Mountingstructure 168 has a lower surface 170, and a predetermined shapedlongitudinal mounting channel 172 primarily utilized for a trailer axleat desired positions along the length of the side structural member 20.This mounting function and its other uses will be described in moredetail below.

[0051]FIG. 9 is a cross-sectional view of a fender mount bracket. Fenderbracket 174 has an upper portion 176 with an upper end 177 and a lowerportion 178 arranged perpendicular to the length of upper portion 176,and each coupled at opposite ends of off-set portion 180. Off-setportion 180 forms a longitudinal channel on the inside surface ofbracket 174, and is used as a wiring run for electrical wiring tooperate lights mounted on an associated fender, and provides room formounting bolt heads that may be utilized in some applications to mountfender supports to bracket 174.

[0052]FIG. 10 is a partial perspective view of a fender mount bracket.Bracket 174 has a predetermined length and is arranged along sidestructural member 20 to a position in proximity to the location ofpositioning the axle-supported wheels 14. The upper end 177 of upperportion 176 is slidably retained in the upper channel 154 and the insideface of upper portion 176 is positioned along face portion 156. Thelower portion 178 is in contact with lower surface 170. One or moreholes 182 are drilled in the lower portion 178 to receive mounting bolts(not shown) to hold bracket 174 in place, along with mounting the wheeland axle assembly to the side structural member 20. Fender supportmembers 184 and 186 are mounted outwardly from bracket 174, and areutilized to support and mount a fender, such as fender 32 to thetrailer. Fender support members 184 and 186 are attached to bracket 174,for example by welding, and are of sufficient strength to support afender and to support steps 36 and 34, respectively. Members 184 and 186have retention channels 188 and 190 along their respective lengths.These retention channels are configured to retain one or more captivenuts (not shown) along these channels, and are configured to cooperatewith one or more bolts (not shown) that pass through mounting structuresin the fender, and when tightened, hold the fender in place. The actualmounting arrangement for bracket 174 will be described in more detailbelow.

[0053]FIG. 11 is a three-dimensional view of a slidable axle and fendermounting member. The axle support member 200 is comprised of an extrudedstructure that is integrally formed having a central portion 202 withthreaded bolt holes 204 and 204′ therein. The bolt holes are utilized toreceive the bolts (not shown) that affix an axle to the assembly. A pairof longitudinal engaging members 206 and 208 are formed at the sides ofthe center portion 202, and are formed with longitudinal channels 210and 212, respectively. Members 206 and 208 have longitudinal channels214 and 216, respectively, with channels 210, 212, 214, and 216configured to mate with protrusions associated ones of the mountingchannel 172 of the side structural member.

[0054]FIG. 12 is an end view of the slidable axle support memberslidably engaged within the mating channel in the side structuralmember. The axle support member 200 is in slidable contact with thelongitudinal channel 172 of side structural member 20. Upper surface ofmounting 168 is slightly concave. This concave structure in conjunctionwith the design of the configured channel is operable as part of thelocking mechanism to lock the axle support member 200 in place when itslongitudinal placement selection is made. An axle and axle bracket (notshown) are affixed to the under surface 170 by passing associated bolts220 (shown broken) through the appropriate threaded apertures 204 and204′. The bolts are selected of sufficient length such that wheninserted and tightened, they impinge on lower surface 222, and whentightened fully, exert upward pressure on mounting structure 168 tocause it to slightly deflect. This deflection produces a torque forcealong the members forming channel 172 and causes mounting protrusions224 and 226 to be urged inwardly to engage channels 210 and 212,respectively. Protrusions 228 and 230 are urged inwardly and upwardly toengage channels 214 and 216, respectively. This clamping action ofmating structures and the hold force of bolts 220 causes the axlemounting member 200 to be firmly locked in place.

[0055]FIG. 13 is a cross-sectional view of a tie down track for use withaluminum bed members. Retention channel 52 has an upwardly extendingchannel opening 240 defined by protrusions 242 and 244. Members 246 and248 are adapted to cooperate with formed edges of aluminum bed panels(not shown) and aid in holding them in place. For plywood bed members,the retention channel configuration illustrated in the identifiedcross-referenced patent application are preferred.

[0056]FIG. 14 is a partial rear view of a wheel, fender, and axleassembly mounted on an adjustable axle support mechanism. To provide thelow profile, wheels 14 are set outside of the edges of bed 12, and aremounted to axle 250. The side structural members 20 are mounted via axlesupport members 200 to axle 250. Additional cross support members 252can be utilized to support multiple bed portions 12. As shown, sideretention channels 162 are provided at each side of the trailer andadditional retention channel 52 is illustrated at the midpoint of bed12. It is of course understood that the retention channel 52 need not beused, or that additional retention channels can be positioned as neededon bed 12. Fender 32 is illustrated mounted to side structural member 20by mounting bracket 174 and held in place by member 178 being bolted toaxle support member 200.

[0057]FIG. 15 is a three-dimensional view of a loop tie down device. Aloop structure 53 is configured to cooperate with any retention channel,and is shown with respect to central retention channel 52. It is ofcourse understood that a loop structure 53 is also utilized with theside retention channels 162. A bolt 260 cooperates with a slidableretention device, which will be described below, and when nut 262 istightened, operates to hold the lower surface 264 of loop 53 in contactwith the upper surfaces 266 and 268 of channel 52, thereby providing asecure mechanism to tie down a load. Though a loop structure is shown,the tie-down could have alternative shapes including but not limited tocletes, hooks, or the like.

[0058]FIG. 16 illustrates a releasable structure for use with a loop tiedown device. A retention member 270 is affixed to bolt 260. Member 270has a first dimension D1 that is wider than the channel opening ofretention channel 52. It has a second dimension D2 that is narrower thanthe channel opening of retention channel. This configuration allows thereleasable structure to be positioned in a first position to cause it tobe retained within the retention channel when nut 262 is tightened; and,when in a second position allows it to be released upwardly andoutwardly through the retention channel opening when nut 262 is releasedand the releasable structure is rotated for releasable alignment. Inthis manner, the tie down loops 53 can be inserted as necessary in theappropriate retention channels, positioned, rotated and the associatednut 262 tightened down. In this manner, the tie down loops 53 can bepositioned as desired along any of the retention channels and can bereadily removed as necessary or desired.

[0059]FIG. 17 is a cross-sectional view of a front structural member.Front member 22 is of a box beam cross section having an upper portion270 extending above the level of the bed 12. An upper surface 272supports an associated bed member. A face portion 274 has a facialridged configuration for additional strength. Front member 22 isassembled with side structural members 20 by welding or other suitablejoining methods.

[0060]FIG. 18 is a cross-sectional view of a rear channel structuralmember 280 having an upward projecting portion 282 to protect the edgeof an associated bed member which is supported on surface 284. Lowerprojection 286 and member 288 form a channel across the rear of thetrailer in which lights and reflectors can be mounted and protected frombreakage. Projection 290 is upwardly extending to provide additionalstrength and provide a juncture 292 that can engage the ground when thebed is tilted and the tilt limiting structure is not lowered. The tiltlimiting loading ramp is mounted to upward projection 282 by matinghinge structures (not shown).

[0061]FIG. 19 illustrates a railing bracket 300 having a horizontalsupport surface 302 and vertical support member 304. A downwardlyextending member 306 and downwardly extending member 308 are positionedto form a channel that rests on the upper portion 152 of side structuralmember 20. A lip portion 310 is positioned to cooperate with a mountingbracket that will be described below.

[0062]FIG. 20 illustrates a railing bottom holding member mounted to aside structural member. Holding member 320 has an upwardly extendingmember 322 arranged to mate with downwardly extending member 306 of therailing bracket 300. A mounting portion 324 has a lower surface 326adapted to be supported upon portion 150 of side structural member 20and to extend across retention channel 162. One or more apertures 328are provided to cooperate with associated releasable structures (seeFIG. 16) to mount the railing bottom holding member to as associatedretention channel.

[0063]FIG. 21 is a broken three-dimensional view of a mounted railingbottom member. The bottom of a railing post 30 is affixed, for exampleby welding, to supporting surface 302 and vertical support member 304 ofthe railing bracket 300. Bracket member 308 encompasses the downwardlyextending portion of raised portion 152 of side structural member 20.Holding member 320 is supported on portion 150 and extends acrossretention channel 162. The holding member 320 has upwardly extendingmember 322 in contact with downwardly extending member 306 of thebracket 300. The structure is held in place by nut 330 that cooperateswith a bolt 260 on a releasable structure retained with retentionchannel 162 by retention protrusions 164 and 166. This arrangementallows an auxiliary railing structure to be affixed to the trailer or tobe removed as desired.

[0064] From the foregoing detailed description it can be seen that thevarious extruded and integrally formed members can be adapted to variouslengths for differing size trailers or different configurations of decksupport structures. Such formation from non-corrosive materials provideslong-lasting structures, greatly simplifies the manufacturing processes,and simplifies the supply of materials for spare parts. The variousfeatures of assembly and slidable adjustments provide substantialbenefits in flexibility of assembly and use in operation.

[0065] Having described the preferred embodiment of the invention inconjunction with the drawings, it can be seen that the various purposesand objectives of the invention have been achieved in the preferredembodiments, and that the best mode has been described. Variousmodifications and extensions will become apparent to those skilled inthe art within the spirit and scope of the invention. Accordingly, whatis intended to be protected Letters Patent is set forth in the appendedClaims.

I claim:
 1. For use as a structural member for a bed supporting framefor a trailer, a side structural member comprising: an elongated bodyhaving a predetermined length, and first and second ends; said elongatedbody along its predetermined length having an upper portion extendingupwardly from said load supporting surface, an outer surface and aninner surface, said upper portion including an upper channel; a faceportion coupled at its upper extremity to said upper portion, and havinga first lower extremity; an elongated retention channel coupled at saidinner surface substantially at the level of a trailer bed, saidelongated retention channel having a first predetermined channel shape,with a retention channel opening upwardly; and an inner member havingits upper extremity coupled to said elongated retention channel andhaving a second lower extremity.
 2. A side structural member as in claim1, and further including a lower channel structure coupled to said firstlower extremity and to said second lower extremity, said lower channelstructure having a second predetermined shape including a mountingstructure with a mounting channel opening downwardly, said lower channelstructure including oppositely disposed ridged mounting surfaces.
 3. Aside structural member as in claim 2, and further including a slidableaxle support member having a predetermined length, a thicknessdimension, one or more threaded holes through said thickness dimension,and oppositely disposed engaging structures having predetermined shapesto mate with and slidably engage said oppositely disposed ridgedmounting surfaces.
 4. A side structural member as in claim 3, whereinsaid side structural member is integrally formed from non-corrosivemetal.
 5. A side structural member as in claim 3, and further includinga fender mounting bracket adapted to be mounted to said side structuralmember in a predetermined relationship with an associated wheel, saidfender mounting bracket including an upper extension having an upperedge engaged and retained by said upper channel, a middle portion incontact with an associated said face portion, and a lower portion at apredetermined angle to said middle portion capable of being arrangedbelow an associated slidable axle support member and adapted to beaffixed thereto.
 6. A structural member as in claim 5, and furtherincluding a pair of fender supports mounted to said fender mountingbracket, each of said fender supports having a predetermined length anda captive nut retaining channel extending along said predeterminedlength to slidably engage one or more captive nuts along said length tocooperate with one or more fender mounting bolts to mount an associatedfender.
 7. A structural member comprising: tie-down means for providingreleasable holding and slidable adjustment of restraints utilized forretaining a load; gripping means for gripping an associated structure;and axle mounting means for providing adjustable positioning andmounting of an associated axle structure.
 8. A structural member as inclaim 7, wherein said structural member is integrally formed from anon-corrosive material.
 9. A structural member as in claim 7, andfurther including: fender mounting means in cooperation with saidgripping means and said axle mounting means for providing adjustablepositioning and mounting of an associated fender.
 10. A structuralmember as in claim 9, wherein said fender mounting means includes:supporting means in cooperative relationship with said gripping meansand said axle mounting means for providing adjustable positioning of theassociated fender; and fender coupling means affixed to said supportingmeans and arranged to support the associated fender.
 11. A structuralmember as in claim 10, wherein said fender coupling means includescaptive nut retaining means for use in affixing the associated fenderthereto.
 12. A structural member as in claim 7, and further including:rack mounting means in cooperation with said gripping means and saidtie-down means for mounting a rack structure.
 13. A structural membercomprising: a beam structure having a predetermined cross-section, firstand second ends, and a predetermined length; a tie-down channel along afirst portion of said beam structure; an axle mounting channel along asecond portion of said beam structure; and a gripping channel along athird portion of said beam structure.
 14. A structural member as inclaim 14, wherein said tie-down channel, said axle mounting channel andsaid gripping channel are spaced apart and are substantially parallel.15. A structural member as in claim 13, and further including incombination: a fender mounting structure having a first support memberhaving a first edge retained by said gripping channel and a second edge,and further having a first mounting member in proximity to said secondedge and positioned to cooperate with said axle mounting channel,whereby said fender mounting structure can be slidably positioned alongsaid beam structure; and second and third support members for engagingand supporting an associated fender, said second and third supportmembers each having a first end affixed to said first support member,and each further having a fender mounting structure.
 16. A structuralmember and combination as in claim 15, wherein each said fender mountingstructure includes a channel along the length of the associated one ofsaid second and third support members, wherein each said channel isadapted to function as a captive nut retaining capacity.
 17. Astructural member as in claim 13 and further including in combination: arack mounting structure having a first structure in cooperativerelationship with said gripping channel, a second structure forsupporting an associated rack structure, and a third structure incooperative relationship with said tie-down channel.
 18. A combinationas in claim 7, wherein said first structure includes a channel adaptedfor slidable engagement of at least a portion of said gripping channel;said second structure includes a first surface for supporting anassociated rack structure and a second surface at an angle to said firstsurface for bracing the associated rack structure; and said thirdstructure includes one or more affixing member, each having a firstportion for engaging said first structure and a second portion forremovably coupling to said tie-down channel.
 19. A combination as inclaim 18, wherein each said affixing member includes a removableengaging member in cooperation with said tie-down channel, whereby eachsaid affixing member can be positioned along said tie-down channel. 20.A combination as in claim 18, wherein said first structure and saidsecond structure are integrally formed.